UCP315 bearing: complete specifications & equivalents
The UCP315 is a JIS B 1559 radial bearing sized 75 x 160 x 82 mm (bore x OD x width) with 2RS sealing. Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 75 mm |
| Outer diameter D | 160 mm |
| Width B | 82 mm |
| Seal / shield | 2RS |
| Basic dynamic load rating C | 126 kN |
| Basic static load rating C0 | 77 kN |
| Fatigue load limit Pu | 5.55 kN |
| Mass | 14000 g |
| Housing height H | 100 mm |
| Housing overall length L | 380 mm |
| Mounting bolt center distance J | 290 mm |
| Mounting hole diameter N | 27 mm |
| Manufacturer designation | UCP315 |
| Standard | JIS B 1559 |
| Catalog version | CAT. No. 2203-3/E 2024 |
| Last verified | 2026-09-25 |
Source: catalog reference (CAT. No. 2203-3/E 2024) · extracted 2026-09-25
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (CAT. No. 2203-3/E 2024); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
Dimensions in inches & UCP-series range
| Bore d | 2.953 in |
|---|---|
| Outer diameter D | 6.299 in |
| Width B | 3.228 in |
| ISO bore code | 15 |
| Radial section height (D−d)/2 | 42.5 mm |
| Smallest bore in UCP-series | 12 mm |
| Largest outer diameter in UCP-series | 300 mm |
| Width range across UCP-series | 31–145 mm |
| Bore position in UCP-series (smallest first) | 15 of 25 |
| Bore above smallest UCP-series size | 63 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| UCP315 | ISO 15 | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | ISO 15 boundary-dimension envelope; seal suffix convention varies by brand (2RS / DDU / LLU / 2RSR) — verify seal design and temperature range. Brand-specific OEM equivalents pending multi-source data. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the UCP315 model number is decoded
The NTN UCP315 unit pairs a UC315D1 sealed ball bearing insert with a one-piece P315 cast-iron pillow block housing, delivered aligned, greased and ready to bolt down. The UCP315 number follows NTN's mounted-unit convention: housing letter P, 3-series section, bore code for 75 mm; P315 and UC315D1 are the separate housing and insert part numbers inside. Shaft size is 75 mm; the cast base stands 100 mm to the shaft centre (H), is 380 mm long overall (L), and the two foundation holes on 290 mm centres (J) clear 27 mm M22 bolts. The 3-series section is the heavy-duty end of the range: a UC3 high-capacity insert in the longest, strongest housing, specified for shock loads and long conveyor centres. The upright base carries the shaft parallel to and above the mounting surface, which is the arrangement fan, conveyor and transmission drives use whenever a plinth or rail is available. Large-bore mounted units like this are selected on calculated bearing life plus foundation quality — the cast base is now a structural part of the drive, not just a convenient clamp. Agricultural machinery — augers, stirrers, bucket elevators — uses this unit in the open, where the contact seals and slinger are the only barrier between the grease and chaff, dust and spray wash. The self-aligning capacity corrects only static misalignment of a few degrees; it does not forgive a bending shaft, which continuously pumps the outer ring and frets the spherical seat. Basic ratings of the UC315D1 insert are 126 kN dynamic and 77 kN static; the assembled UCP315 weighs about 14.0 kg.
Typical equipment & failure modes
Common applications
- process fans and induced-draft drives
- quarry feeder and transfer drives
- sawmill arbors and feed rolls
- continuous one-direction running where creep risk concentrates on the setscrew points
Known failure patterns
- insert brinelling from hammer mounting or from belt tension applied to a stationary unit
- over-greasing that churns the charge, overheats the bearing and blows the seal lip
- cracked cast ear from mounting on an uneven face and pulling one bolt fully first
Selection pitfalls — read before you substitute
- UCP315 is located on the shaft by setscrews only; for shock reversing drives consider an adapter-lock insert family instead, since setscrew points indent the 75 mm journal over time.
- UCP315 at 75 mm uses M22 bolts that need a torque wrench and a cross pattern; pulling one bolt first tips the 100 mm centre height and binds the insert.
- The 3-series insert makes UCP315 the highest-rated unit at 75 mm; its advantage disappears on a soft foundation, so spend the saved margin on base stiffness rather than skipping shims.
- As a pillow block, UCP315 needs a prepared horizontal surface at the 100 mm centre height: shim both feet with full-width packs so the 380 mm base seats over its full area.
- At replacement time, measure the 75 mm shaft journal — a worn or deeply indented journal under the setscrews will let a brand-new UCP315 creep identically to the old one.
Frequently asked questions
When should I choose a pillow block like UCP315 instead of a flanged unit?
Choose the UCP315 pillow block when the shaft runs parallel to a horizontal base plate, rail or plinth — the upright housing holds the shaft centre 100 mm above the 380 mm bolt-down base. Choose a UCFL flange when the shaft meets a vertical frame face and the housing bolts flat against it.
What loads can the UCP315 unit carry?
The UC315D1 insert is rated at 126 kN dynamic and 77 kN basic static (fatigue load limit 5.55 kN). Mounted units are predominantly selected on radial load from belt pull and overhung weight; axial capacity is limited and should be checked separately.
What are the dimensions of an UCP315 mounted bearing?
UCP315 takes a 75 mm shaft (insert UC315D1, 160 mm OD) and has a unit mass of about 14.0 kg. Housing figures: centre height H 100 mm, length L 380 mm, bolt centres J 290 mm, foot holes 27 mm for M22 bolts.
What does the UCP315 designation mean?
UC identifies the wide-inner-ring, setscrew-locking ball bearing insert; P the upright pillow block housing; 3 is the duty series; the last digits encode the 75 mm bore. UCP315 is built from housing P315 plus insert UC315D1 (D1 = greasable).
How is UCP315 locked to the shaft, and how tight should the setscrews be?
The UC315D1 insert uses two collar setscrews on the 75 mm shaft. Tighten them to NTN's torque table for this bore size in sequence — half torque on the first, full on the second, then back to the first — and re-torque after the first 24–48 running hours once the collar has seated.
Reviewed & verified by the MPN Base engineering desk against source catalog CAT. No. 2203-3/E 2024 on 2026-09-25. Read our editorial & correction policy.